Process of making chlorin compounds of tin.



N0. s1o,45s. i P ATBNTBD JAN. 2s, 1906. A c; E; AGKER.

PRoQBss 0F MAKING GHLORIN COMPOUNDS 0F TIN. APPLICATION FILED DB0.30.1903.1 BEIEWED JUNE 14., 1'905.' l

' UNITED STATESATI ENT OFFICE.

CHARLES E. ACKER, OF NIAGARA FALLS, NEW YORK, ASSlGNOR TO AClxER PRGC/ESS COMPANY, A CRPORA'llON OF NEW JERSEY.

Pnocsss oF MKiNe. cercana CoMPouNDs oF TiN.

Specification of Letters Patent.

,Patented Jan. 23. 190e.

' ApplicationiledDecember 30, 1903. Renewed .Tune 14, 1905. Serial No. 265,239.

To @ZZ whom it may concern.-

.' chlorid to stannic chlorid by Be it known that l, CHAR-Lus E. Acura, a citizen of the United. States, residing at Niagara Fallsin the county of Niagara and State of New York, haveinvented certain new and usei'ul improvements in Methods of Making Chlorin Compounds oi' Tin, oi which the following is a specification.

This invention is a method of making chlorin compounds oi tin.

Heretoiore it has been customary to prei pare stannic-chlorid solutions by reacting upon metallic tin Withhydrochloric acid in solution, thereby forming stannous chlorid, and subsequently converting said stannous addition of potassium chlorate tothe acid solution. This process is relatively expensive, since the chlorin is derived from the comparatively costly compounds hydrochloric acid and potassium chloratef and is furthermore subject to the disadvantages that the solutions produced cannot in practice exceed a density of to 51 Baume and are contaminated by the presence of considerable quantities of potassium ,chlorid derived from the reduction of the chlorate. Furthermore, it is impractical to concentrate such solutions by reason of the loss of stannic' chlorid by volatili/'nation and the tendency oi the solutions to become basic. Solutions of a densit'y of 600` Baume have been prepared by first producing a solutionof stannous chlorid, concentrating the same to saturationand subsequently converting it, by means of potassium chlorate, to stannic c lorid but this process is an expensive one, `and thersolutions obtained are also contaminated by potassium chlorid.

f I have discovered that stannic-clilorid solutions of high concentration and uncon 'ta'rninajt'edl by impurities-oic any kind maybe 'produced by .circulating a solvent containing 'chlorin successively and repeatedly in' contact With metallic tin and in contact with a reagent capable oi converting the tin in solution from the divalent' to the tetravalent. stat-eand have claimed such process in my copending application, Serial No. 160,564, filed June 8, 1903. i have also discovered that if such stannic-chlorid solutions having a speciiic gravity equal to` or vexceeding '1.80 be converted by contact with metallic tin to `stannous-chlorid solutions cfa corresponding concentration the ystannous chlorid will sepa' Vaction-tower, which may rate from said solutions in' the form of crystals of a high degree of purity. Such process I have claimed in my copendingapplication, SerialNo.'160,5.65, iiled June 8,1903;

` In my \co ending; application, Serial No. 160,566,ile June' 8, 1903, I have described and claimed an ap aratussuitable for carrying out eitherof t e above-mentioned lprocesses, said apparatus comprising, essentially, a dissolving vessel for-metallio tin, a reaction tower or vessel in operative connection therewith, and Va suitable source of chlorin `or of chlorin and hydrochloric acid communicating with said reaction-tower.

- l have now discoveedthat in order to secure the'best results' with the greatest .economy of operation it is necessary to maintain such conditions as will prevent the substantial formationland accumulation in the solution of metastannic compounds.) I have ob# served a strong heating eli'ect dueto the solur tion of the tin and a further strong heating 'eiect due to its conversion from the divalen'i to the tetravalent state, the combined effect being .suilicient to cause a rapid increase u1 the tem erature of the circulating solution. l have ound that such increase is accompanied by a tendency to the formation of metastannic compounds andthat by operating under conditions as hereinafter stated any serious accumulation of suchmetastannic compounds in the solution may be avoided.

For afull understanding of my invention reference is made to the accompanying dran'- ing, wherein one formiof apparatus suitable for carrying my process into eiect 1s shown in vertical section'. v,

Referring to the igure, 1 represents va rebe .ot any suitable type. It is here indicatedas comprising a series'fof superposed stoneware Vsections 2, provided with perforated distributing-plates 3 andhereinafter referred to as reaction-sections. 'In the uppermost section is a distributing device for the inflowing liquid, comrising a receiving` vessel 4, an inlet-pipe eading to a point near the bottom thereof, and a pluralitvlof discharge orifices o'rtubes 6 6, the whole being supported by a distributing-plate 7.

8 9 represent, respectively, the inlet and outlet for chlorin or the gaseous mixture con taining chlorin, hereinafter incre fullyI described. 1

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Vio -lictin v'Which e whiz@ zffi'ieansand from which it is permitted to rei indicates cooling-sectiensrof the tower interposed between the lseveral reaction-sect tions 2;. Said lsections 10 are-indicated as T provided with means fer causing y.water or 5 other cooling medium't'o circulate lbetween f ,dnd around short vertical tubes 11, which .,g lCOIII'mlmiOate with upper and lower reaction- `sectionsl 12 represents a dissolving-tank for metalv r may conveniently comprise a glazed-'stoneware vessel supported at or near th-topof a'solution-tank 13 and provided Ahear litsktop with a series of orifices 14.,

. .`.Mea;ls.are provided, as shown, for conducting thesolu'tion from the reaction-tower to the dissolving-tank and, if desired, for disl the solution therein. 1

`I'15 vre rsents an elevated receiving vessel the 'solution is raised by suitable through ipe 16 to the reaction-tower. s .one suitable means for raising the solution I-,have indicated an airlift comprising 'a `pipev 17, immersed to a suitable depth inthe a5 so ution in tank 13, and an airinjection pipe f ,18 in operative relation therewith.

I have shown the dissolving-tank 1 2 as supported near the surface of the solution in 13.,.flhis possesses the special advantage o thattlie rise of temperature of the liquid due to the solution of the tin is thereby mininiized, the I heat being lrapidly dissipated.

rlln's is important for the avoidance of the e formation of metastannic compounds, as will, more clearly appear. I

` '.lhe constructionand arrangement of the apparatus may be widely varied, it being essential only that effective means be provided for cooling the circulating solution. Instead 4o of or in 'addition to the cooling-sections in the reaction-tower yI may, for instance, cool the li ruidatany part of the circuit, or a part o' ll ofthe necessary cooling may be accomplished by 'a' sufiicient reduction in the temperature of the reacting gas, or, if desired,

the solution mi ht be sufficiently cooled by `exposing extended surfaces to the action of the atmosphere. This cooling effect is aided by the use of dilute chlorin, as hereinafter demetallic tin, the metal passing intol solution and the solvent liquid 'ueing'reducedvwholly or in part to the divalent state. The liquid having thus lost its solvent power for tin-is thereu on brought into contact with chlorin gas,AW ereby it is again raised lto the tetravto alent state. with corresponding restorationof its solvent power.-- This regenerated'solvent is again brought into contact Withmev Atallic tin and again' regeneratedthe operation proceeding in this manner until .the required. concentratiqririreachedgiwherupon ther specific conditions above described I have sienne the stannic-chlorid solutiodis Withdrawn from the system, an' e uivalent amount of water or a suitable chlorld solution being added, and the process. continued as before. If

desired, the process may be made continuous by the gradual withdrawal' of the tin-chlorid solution and the addition of corresponding quantities of water or chlorid solution. -To obtain the solution containing the tin inthe tetravalent condition, it should be withdrawn from the system at a point immediately following the treatment with chlorin.

lf the liquid contains an excess of chlorin,

said excess isremoved by the careful addition of stannous chlorid, and a clear, pure, colorless, and dense solution is obtained. To obtain a solution containing the tin in the divalent condition, it may be Withdrawn from the system at a point immediately following the treatment with metallic'tin, or, if desired, fthe' solution may be Withdrawn 'as stannic chlorid, and subsequently subjected in a separate `vessel to the action of metallic tin to convert it into stannous chlorid. From solutions so produced the stannous chlorid will separate 1n the form of crystals of a high degree of purity, and if the stannous-chlorid solutionis formed at a temperature above thevnormal a large yield ofthe crystals Will be (btained when the solution ispcrmitted to coo The ypresence of metastannic salts is par-- ticularly' injurious in the production of stannic chlorid. The stannlc-chlorid solution produced as abovedescribed containsl some free chlorin7 and this is most conveniently removed by the careful addition, as above mentioned, of stannous, chlorid. Under. these conditions, however, aslight excess of stannous chloridis often added, and such Stannous salt in presence of a metastannicl compound develops a yellow or brownish tint in the product. g -f 5 The precise degree of temperature at which the circulating solution should be maintained is dependent to some extent upon the specific conditions of the operation*as, for instance, the concentration of the solution and the degrec of dilution of th'e'chlorin gas. Under foun it advisable to maintain between 40- and 60 centigrade. Y j l find that it is not'necessary to use pure chloringas for theconversion of the tinfrom its dival'ent to its tetravalent state, but y that the gas may contain a large proportion of air or oxygen. I-have also found that the reac-y tion is facilitatedby the-injection of steam into the chlorin, with the consequent forma they solution "cion, ofhydrochloricacid, or by the use of 125 chlorin containing drochlorlc acid;

a certain proportionnf hy-4 lI 'have employed4 a; gaseous-mixture con- `taining nineigeive toi'ninetyesix ,per cent.k of air, lfour to vel-,per eentqiofgchlormjand ally A small percentage of `that a portion ct heat evolved by t use ot dilute chlorin pesscssesy A gas possessing the general characteristics above referred to is conveniently producedby the-operation of my electrolytic cell substantially as described in my prior patent, No. 674,691, issued May 2l, 190i. The conduit 8, above described as an inlet vfor the gas Which serves to convert the tin from the divalent to the tetravalent state, may be therefore the outlet of the-electrolytic cellin which chlorin is produced.

It'will beobvious that the character of the original liquid which under the conditions of my process is to become a solution of stannic chlorid may be considerably varied. Thus Water may be employed or any desired pro- Dortion of stannic chlorid, stannous chlorid,

ydrochloric acid, or other suitable compound may be addedthereto.

l claim- Y l l. The herein-described method of making chlorin. compounds of tin7 which consists in subjecting a solvent for tin to the'alternate action of metallic tin and chl orin, and cooling the solution, whereby the tendency to pro duce metastannic compounds is avoided, substantially as described.

2A The herein-described method of making chlorin compounds of tin, which consists in subjecting a solvent for tin to the alternate and repeated action of metallic tin and 'tendency to produce "itz, cooling 'the solution,` whereby metastannic comu 'pounds is avoided, substantially as described.

3. The hereiindescribed method of vmaking chlorin compounds et tin, which consists in subjecting a solvent :tor tin to the alternate action ot n'ietallic tin and a gaseous mixture containing chlorin, .and cooling the solution, whereby thetendency to produce inetastannic compounds `,is avoided, substantially as describe v t. The herein-described method of making chlorln compounds of tin, which consists in subjecting a solvent for tin to the alternate and repeated action Aof metallic tin and agase ous mixture containingJ chlorin, and cooling the solution, whereby the tendency to pro'' duce metastannic compounds is avoided, substantially as described.

5. The herein-descrilied` method ofmaking clilorin compounds of tin, which consists in subjecting a solvent for tin to the alternate action of metallic tin and a gaseous body con# taining chlorin, and cooling the solution by a medium out ot' contact therewith, whereby the tendency to produce nietas'tannic comf. pounds is avoided, substantially as described.

6. The herein-descri bed method of making chlorin compounds ol. 1. which consists in subjecting a solvent. to in to the 4alternate and repeated action of metallic tin and agaseous body containing chl i, and cooling the solution'by medium o ci contact therewith, whereby the l',endencj\v to produce metastannic compounds is avoided, substantially as described.

In testimony whereof l affix my signature in presence of two Witnesses.

CHARLES l. ACKER. 

